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We present multi-epoch optical spectroscopy of seven southern Fermi-monitoredblazars from 2008 - 2013 using the Small and Medium Aperture Research TelescopeSystem (SMARTS), with supplemental spectroscopy and polarization data from theSteward Observatory. We find that the emission lines are much less variablethan the continuum; 4 of 7 blazars had no detectable emission line variabilityover the 5 years. This is consistent with photoionization primarily by anaccretion disk, allowing us to use the lines as a probe of disk activity.Comparing optical emission line flux with Fermi $\gamma$-ray flux and opticalpolarized flux, we investigate whether relativistic jet variability is relatedto the accretion flow. In general, we see no such dependence, suggesting thejet variability is likely caused by internal processes like turbulence or shockacceleration rather than a variable accretion rate. However, three sourcesshowed statistically significant emission line flares in close temporalproximity to very large Fermi $\gamma$-ray flares. While we do not havesufficient emission line data to quantitatively assess their correlation withthe $\gamma$-ray flux, it appears that in some cases, the jet might provideadditional photoionizing flux to the broad line region, which implies somegamma-rays are produced within the broad line region, at least for these largeflares.

astrophysical journal/the astrophysical journal

The SMARTS Multi-epoch Optical Spectroscopy Atlas (SAMOSA): Using  Emission Line Variability to Probe the Location of the Blazar Gamma-emitting  Region